The U.S. Is Left Behind on Trade

The new Japan-EU deal will hurt a slew of American exporters.

Europe and Japan finalized a trade deal late last week that shows how Donald Trump’s protectionism will harm American companies and farmers. The agreement eliminates tariffs on more than 95% of products and reduces nontariff barriers. Europeans will gain access in particular to Japan’s lucrative agricultural markets that the U.S. lost by walking away from the 12-nation Trans-Pacific Partnership trade pact.

And that may be the point. Having staked his economic reform agenda on the Pacific trade deal, or TPP, Japanese Prime...